Carvedilol Increases Atrial Natriuretic Peptide Plasma Levels in Hypertensive Patients

Abstract

Twenty five patients with moderate essential hypertension were studied for 30 days in order to evaluate the medium term effects of carvedilol on atrial natriuretic peptide (ANP) levels. This drug blocks the β 1 and β 2 adrenenergic receptors as well as α 1 adrenergic receptors. In addition, it has strong antioxidative and antiproliferative properties. The drug was given orally at a dose of 12.5 mg b.i.d. Quantitative determination of human ANP was made by radioimmunoassay procedure (RIA). At the end of this clinical trial, mean plasma levels of ANP had risen during treatment by 21.18% (from 37.60 pg/ml to 45.83 pg/ml) while both systolic (SBP) and diastolic (DBP) blood pressure as well as diameters of the left cardiac cavities had decreased in a statistically significant way. The ratio ANP/SBP was also increased by 46.6% in a statistically significant way. These findings support the suggestion that the increase in plasma ANP following the administration of β-adrenergic blockers to hypertensive patients is a primary effect of beta blockade and not a mechanical one secondary to a negative inotropic action on the left ventricle and obviously contributes to the anti-hypertensive action.